Examine source code of Unit Price Shopper

{
  "manifest_version": 3,
  "name": "Unit Price Shopper",
  "version": "2.2.5",
  "permissions": [
    "storage"
  ],
  "description": "Filters items on Amazon, Walmart, and Albertsons brand pages (Albertsons, Safeway, etc.) by unit price.",
  "content_scripts": [
    {
      "matches": [
        "*://*.amazon.com/*",
        "*://*.amazon.ca/*",
        "*://*.amazon.co.uk/*",
        "*://*.amazon.de/*",
        "*://*.amazon.fr/*",
        "*://*.amazon.it/*",
        "*://*.amazon.es/*",
        "*://*.amazon.co.jp/*",
        "*://*.amazon.cn/*",
        "*://*.amazon.in/*",
        "*://*.amazon.com.mx/*",
        "*://*.amazon.com.br/*",
        "*://*.amazon.com.au/*",
        "*://*.amazon.nl/*",
        "*://*.amazon.se/*",
        "*://*.amazon.pl/*",
        "*://*.amazon.sg/*",
        "*://*.amazon.com.tr/*",
        "*://*.amazon.ae/*",
        "*://*.amazon.sa/*",
        "*://*.amazon.com.be/*",
        "*://*.amazon.eg/*",
        "*://*.amazon.lu/*",
        "*://*.amazon.at/*",
        "*://*.amazon.ch/*",
        "*://*.amazon.ie/*",
        "*://*.amazon.co.nz/*",
        "*://*.amazon.co.za/*"
      ],
      "js": [
        "amazon/content.js"
      ],
      "run_at": "document_start"
    },
    {
      "matches": [
        "*://*.walmart.com/*",
        "*://*.walmart.com/browse/food/*",
        "*://*.walmart.ca/*",
        "*://*.walmart.ca/browse/food/*"
      ],
      "js": [
        "walmart/content.js"
      ],
      "run_at": "document_start"
    },
    {
      "matches": [
        "*://*.albertsons.com/*",
        "*://*.acmemarkets.com/*",
        "*://*.balduccis.com/*",
        "*://*.andronicos.com/*",
        "*://*.carrsqc.com/*",
        "*://*.haggen.com/*",
        "*://*.jewelosco.com/*",
        "*://*.kingsfoodmarkets.com/*",
        "*://*.pavilions.com/*",
        "*://*.randalls.com/*",
        "*://*.safeway.com/*",
        "*://*.shaws.com/*",
        "*://*.starmarket.com/*",
        "*://*.tomthumb.com/*",
        "*://*.vons.com/*"
      ],
      "js": [
        "albertsons/content.js"
      ],
      "run_at": "document_start"
    }
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "action": {
    "default_popup": "amazon/popup.html",
    "default_icon": {
      "16": "images/icon_16.png",
      "48": "images/icon_48.png",
      "128": "images/icon_128.png"
    }
  },
  "options_ui": {
    "page": "options.html"
  },
  "icons": {
    "16": "images/icon_16.png",
    "48": "images/icon_48.png",
    "128": "images/icon_128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{7e3f621a-cf8d-47a8-b68f-92b09e6f8821}",
      "strict_min_version": "109.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "sidebar_action": {
    "default_panel": "amazon/sidepanel.html",
    "default_icon": {
      "16": "images/icon_16.png",
      "48": "images/icon_48.png",
      "128": "images/icon_128.png"
    },
    "default_title": "Unit Price Sidebar",
    "open_at_install": false
  }
}